Abstract: In this study, the influence of matrix polarity on the release of characteristic sulfur-containing aroma compounds from vacuum freeze-dried Toona sinensis buds was investigate using sensory evaluation, electronic nose, gas chromatography-ion mobility spectrometry (GC-IMS), and gas chromatography-mass spectrometry (GC-MS). GC-MS results showed that 11 characteristic sulfur-containing compounds were released from the vacuum freeze-dried material after treatment with water, with a total content of (75.26 ± 4.8) µg/g (85.65% of that of fresh T. sinensis). In contrast, these compounds were not detected in the samples treated with solvents of medium to low polarities (methanol, ethyl acetate, or cyclohexane). Furthermore, electronic nose and GC-IMS results indicated that the odor profile and volatile composition of vacuum freeze-dried T. sinensis following water treatment were remarkably similar to those of fresh T. sinensis. This study revealed the crucial role of high-polarity matrices in the release of characteristic sulfur-containing compounds from vacuum freeze-dried T. sinensis. This provides a novel technical approach for releasing the unique aroma of dried T. sinensis and offers technical support for the targeted flavor regulation and application of processed T. sinensis products in multicomponent food systems.

Key words: vacuum freeze-dried Toona sinensis; matrix; flavor; sensory evaluation; electronic nose; gas chromatography-ion mobility spectrometry; gas chromatography-mass spectrometry